✨ add gitmoji-aware commit message generation

[SOUMITRO-SAHA]

• Read t3code.commitMessageStyle from git config to switch prompt style
• Wire GitCore into CodexTextGeneration runtime/test layers
• Add coverage for gitmoji/conventional fallback cases and new feature docs

What Changed

This PR adds support for gitmoji-style commit messages by reading git configuration and adjusting the AI prompt accordingly.

Implementation:

• Read t3code.commitMessageStyle from git config during commit message generation
• Wire GitCore service into CodexTextGeneration layer to access config
• Conditionally modify AI prompt based on config value:
  • gitmoji → Include gitmoji emoji instructions and examples
  • conventional or unset → Use conventional commit style
• Handle case-insensitive matching and partial matches (e.g., use-gitmoji)
• Add 8 comprehensive test cases covering all config scenarios
• Add user documentation in docs/features/gitmoji-support.md
  Files changed:
• apps/server/src/git/Layers/CodexTextGeneration.ts - Core implementation
• apps/server/src/git/Layers/CodexTextGeneration.test.ts - Test coverage
• apps/server/src/serverLayers.ts - Layer composition
• docs/features/gitmoji-support.md - User documentation

Why

Addresses #638 - Users requested gitmoji support to keep generated commits consistent with repos that already use gitmoji. This is especially useful for teams that have adopted gitmoji as part of their workflow.

Approach:

• Configuration-based: Users opt-in via git config (no breaking changes)
• Backward compatible: Defaults to conventional style when config not set
• Flexible: Supports repository-specific and global configuration
• Safe: Handles invalid config values gracefully with fallback to conventional

UI Changes

N/A - This is a backend-only change. The generated commit messages will include gitmoji emojis when enabled.

Checklist

• This PR is small and focused
• I explained what changed and why
• I included before/after screenshots for any UI changes
• I included a video for animation/interaction changes

---

Example:

Before:

add gitmoji feature documentation

- Add comprehensive guide in docs/features/gitmoji-support.md
- Document enable/disable commands
- Include commit examples with and without gitmoji
- List supported gitmoji emojis
- Note platform availability (web, desktop)

After:

✨ add gitmoji-aware commit message generation

- Read `t3code.commitMessageStyle` from git config to switch prompt style
- Wire `GitCore` into `CodexTextGeneration` runtime/test layers
- Add coverage for gitmoji/conventional fallback cases and new feature docs
- Add comprehensive guide in docs/features/gitmoji-support.md
- Note platform availability (web, desktop)

Note

Add gitmoji-aware commit message generation modes to commit workflow

• Adds a commitMessageMode parameter (standard, auto, gitmoji, custom) to the commit generation pipeline, from the API contract through to the AI prompt builder in CodexTextGeneration.
• In auto mode, GitCore.getRecentCommitMessages inspects recent non-merge commits and a new analyzeCommitPatterns utility detects emoji prefixes, scopes, and conventional types to inject a representative example into the prompt.
• In gitmoji mode, emoji guidance is added to the prompt; in custom mode, the user-provided commit message is forwarded as a template/instructions rather than used as the final commit.
• Adds a CommitModeSelector UI component to the commit dialog, with predefined custom templates sourced from a new commitTemplates contract package.
• Risk: CodexTextGeneration now depends on GitCore at runtime; misconfigured layer wiring will cause generation to fail.

^{Macroscope summarized 4b5ed82.}

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[binbandit]

I feel like this is not the best way to do this, nor should we?

I believe we could instead tailor the prompt to give the ai a snippet of some of the previous commit messages, and ask it to follow the same detected style. This way we can ensure that we support the majority of commit message patterns without hard-coding anything like this.

@t3dotgg Do you have an plans around this kind of work that you want to weigh in with?

---

My above "solution" would work to resolve:

• Add option to make commit messages follow Conventional style including scopes #656
• Support gitmoji in generated commit messages #638
• More to come i'm sure

[SOUMITRO-SAHA]

Hi @binbandit , thanks for the suggestion and sorry for the delayed reply. I did not receive the notification earlier and only noticed your comment while reviewing my PRs today.

Your idea about adapting the prompt using a few previous commit messages to detect and follow the existing style makes sense. That approach would likely make the system more flexible and avoid hard-coding behaviour for specific commit formats.

When I originally implemented this change, I interpreted the issue as requesting a switchable feature (enable/disable). Because of that, I added the configuration option to explicitly control the behaviour. My goal was to provide a straightforward solution that satisfies the requirement described in the issue.

However, I agree that dynamically inferring the style from recent commit messages could be a cleaner and more scalable approach. It would allow the tool to support different commit message conventions (with emojis, without emojis, conventional commits, etc.) without needing explicit configuration.

Before making further changes, I would like to confirm the preferred direction with the maintainers. Would you prefer that I update this implementation to follow the prompt-based approach you suggested, or should the configurable switch remain the intended solution?

Happy to adjust the implementation based on the maintainers’ guidance.
Thanks again for the feedback.

[binbandit]

@juliusmarminge until I get knighted, you wanna speak to this?

[UtkarshUsername]

I believe we could instead tailor the prompt to give the ai a snippet of some of the previous commit messages, and ask it to follow the same detected style.

I agree. This would be the best way to do it. It will support people's different preferences, without forcing any pattern on them.

[SOUMITRO-SAHA]

I have tested the implementation locally and everything is working as expected.
Feel free to test it on your end as well and let me know if you notice anything that needs improvement.

Hi @binbandit @juliusmarminge

This PR improves commit message generation by analysing previous commit messages more efficiently.
To reduce token consumption, I implemented analyzeCommitPatterns.ts, a regex-based analyser that detects the basic structure of existing commit messages. This allows us to avoid sending the entire commit history to the AI, which would otherwise consume more tokens during generation.

Because of this, I adopted a pattern-aware prompt optimisation approach, using only one high-quality example in the prompt to guide commit message generation.

Instead of passing 10+ raw commits, we select the single best example using the following priority order:

Priority Order:

1. Emoji + Type + Scope (most structured)
      ✨ feat(git): improve commit pattern detection logic
2. (Emoji + Type) OR (Type + Scope)
    🐛 fix: handle empty commit history safely
    OR
    feat(commit): support emoji detection
3. Any Single Pattern
    📚 update documentation
4. First Commit (fallback)

One well-structured example is often more effective than many mixed-quality examples.

Test Coverage for analyzeCommitPatterns

Added 31 comprehensive tests, covering:

• All pattern combinations (emoji + type + scope, etc.)
• One-line commits
• Edge cases (empty messages, special characters, code blocks)
• Real-world mixed styles

Test Results
✓ 31 tests passed
✓ Edge cases covered
✓ Type safety ensured

Quick Test Commands

# Test only the pattern analysis (31 tests)
cd apps/server && bun run test analyzeCommitPatterns.test.ts

# Test the Codex text generation (13 tests)
cd apps/server && bun run test CodexTextGeneration.test.ts

[juliusmarminge]

Some thoughts after reading the conversation (haven't read code)

• Why a git config and not an app level setting? (ref move some settings to server authorative #1033 for the need for server based config)
• Is past-repo-conventions the only supported option here? For reference, we probably wanna move this repo to using conventional commits but there's pretty much none of those in the history so this would not work for t3code repo as is.
  • I'm thinking (maybe a bit longer term but don't wanna make decisions now that makes those plans more difficult down the road) is to have different options, like gitmoji, conventional commits, infer from repo, and custom (user can write free form text that we put in the prompt)
• We should consider how this affects PR title/body generations (people will wanna configure at least PR titles as well so the whole system feels uniform.
  • Potentially also branch name generations

Don't wanna put all this on you, but also kinda reluctant to make some half-baked solution that we end up throwing away in a week

[SOUMITRO-SAHA]

Hi @juliusmarminge ,

In this PR, we are no longer setting up or updating any Git configuration. Based on our previous discussion, I have fully migrated the implementation so that it only analyses past commit messages and generates a new commit message based on those examples. In short, this PR does not modify Git config at all; it only considers previous commit messages to infer and generate the next commit message.

After reading your reply, it became clear that you are absolutely right about keeping configuration strictly on the server side.

With that in mind, I would like to propose a slightly different approach.

Proposed idea (UI based selection):

The commit message generation style would depend on the mode selected by the user, giving them full control over the output.

Modes:

• Auto → (Default Mode) This will follow the current flow.
  It analyses past commit messages, selects the best example, and then passes that example to the prompt generation step (infer from repo).

• Gitmoji → Generates commit messages using Gitmoji while still following a conventional commit style.

• Conventional → Generates commit messages strictly following the conventional commit format with predefined instructions.

• Custom → Opens an input field where the user can provide their own example or prompt.
  In this mode, the user's input will have the highest priority while still following the conventional structure.

Note: The Conventional flow refers to the instruction format currently used in the main branch.

I have attached a small UI example to illustrate this idea.

Please let me know if you think this approach is reasonable. If it looks good, I can proceed with implementing it.

Also, if you would like me to include the new branch generation logic in this PR as well, please share some guidance or requirements so that I can incorporate that change here too.

[SOUMITRO-SAHA]

Hi @juliusmarminge and @binbandit ,

I'm excited to share this pull request, which introduces a comprehensive commit message generation engine

This feature gives users full control over their commit message style, moving beyond the standard format.

Here’s a breakdown of the new capabilities:

• Multiple Commit Message Styles: Users can now choose from several generation modes:

  • Standard: The existing default behaviour
  • Auto: Intelligently analyses past commits to determine the most likely style (e.g., conventional, gitmoji)
  • Gitmoji: Generates commit messages with gitmoji prefixes
  • Custom: Allows users to leverage predefined templates
  • Direct Message: Uses the user's input directly as the commit message

• Backend-Driven: The entire workflow is handled on the backend. Users simply trigger the "Generate Commit" action, and the server manages the selected mode without any client-side configuration.

• Extensible by Design: The architecture is highly scalable, making it easy to add new features. For example, we can extend the custom mode to support user-defined templates in the future.

• Intuitive User Interface: The UI is designed to be simple and clear, following the project's existing standards. The new options should be easy to understand without extra documentation.

This PR has grown from a small feature into a robust "commit machine" based on our previous discussions. Given the scope of the changes, I’ve taken extra care with testing. I reviewed the implementation using AI tools (Claude 4.6, Gemini 3.1 Pro, and z.ai 5) and added thorough test cases to cover the functionality.

I’ve attached a demo video below to show everything in action:

Fingers crossed this adds real value to the project 🤞 Looking forward to your feedback. Please let me know if you have any questions or suggestions.